CALL: FIT_MATHIESON
The distance between anode and cathode. The anode is assumed
to be the place where the avalanches take place. The strip
width is derived from the bin width of the input histogram.
This parameter is mandatory, and should be entered in cm.
If the fit is successful, then this parameter contains on
return the reconstructed track location in cm. The coordinate
system is the same as the horizontal axis of the input
histogram.
This parameter should be modifiable and its value prior to
the call is not used. Any matrix, histogram or string
associated with it before the call is lost.
Contains on return, if the fit is successful, the normalisation
of the fitted Mathieson distribution.
This parameter should be modifiable and its value prior to
the call is not used. Any matrix, histogram or string
associated with it before the call is lost.
If the FITK3 option is specified, then this argument contains
on return of a successful fit the K3 parameter that matches
best the histogram. If a value is given on entry, then this
value will be used as starting point for the fit. Otherwise,
an initial value of 0.5 is taken.
The argument must in this case be modifiable. Any matrix,
histogram or string associated with it before the call is
lost.
If the NOFITK3 option is specified, then this argument must
contain on entry your prefered value of K3. The argument is
then not modified and the corresponding error is set to 0.
The errors returned are the square roots of the diagonal elements
of the covariance matrix, multiplied by a correction factor equal
to:
sqrt(chi**2/(#points - #parameters))
This correction factor is equal to 1 if the errors to the data
points have been assigned correctly.
These arguments must be modifiable, that is, they can neither be
constants nor expressions.
The options string may contain the keywords listed in the table
below. The keywords should be separated by blanks or commas.
Additional text may be added - no error message will be issued
if unrecognised keywords are used.
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Option Meaning Defaults
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EQUAL Assume equal weight of all points Default
FITK3 Fits the K3 parameter Default
NOFITK3 Keep the K3 parameter fixed Not default
NOPLOT Don't plot the histogram and fit Default
NOPRINT Don't print details during the fit Default
PLOT Plot the histogram with fit Not default
POISSON Assume Poisson errors Not default
PRINT Print details during the fit Not default
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Keyword index.
Formatted on 10/11/98.